Passification of Electrohydraulic Valves Using Bond Graphs
نویسندگان
چکیده
In many applications that require physical interaction with humans or other physical environments, passivity is a useful property to have in order to improve safety and ease of use. Many hydraulic applications (e.g. a human operated excavator) fall into this category. In a previous work, the passivity property of a directional hydraulic flow control valve, and methods for making the valve in a passive two-port system were proposed. In this paper, the problem of developing passifying control laws for directional control valves is re-visited from a bond graph perspective. Two new bond graph elements with power scaling properties are first introduced and the passivity property of bondgraphs containing these elements are investigated. Then by representing the control valve in a suitable augmented bond graph, and by replacing the signal bonds with power scaling elements, it is shown that passifying control laws can easily be recovered and generalized.
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